Leases - Schedule of Future Payments (Details) $ in Millions	Jan. 31, 2020 USD ($)
Operating Lease Maturity
2020 (excluding the six months ended January 31, 2020)	$ 30
2021	74
2022	69
2023	61
2024	59
Thereafter	79
Total future minimum lease payments	372
Less imputed interest	(29)
Present value of lease liabilities	343
Sublease Income Maturity
Remainder of fiscal year 2020	11
2021	22
2022	10
2023	1
2024	1
Thereafter	$ 1

Amount of lessee's undiscounted obligation for lease payments for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of lease payments to be received by lessor in fifth fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981

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Amount of lease payments to be received by lessor in fourth year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in remainder of fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981

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Amount of lease payments to be received by lessor after fifth fiscal year following latest statement of financial position date for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in third fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lease payments to be received by lessor in second fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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